1. Field of the Invention
The present invention provides a projector apparatus comprising a color wheel module, and more particularly, to a projector apparatus capable of switching between displaying a stereoscopic image and a planar image.
2. Descriptions of the Related Art
With the development of image processing technologies, image presenting technologies have evolved from conventional planar projections to stereoscopic projections. As compared to planar projection technologies, stereoscopic projection technologies work under the following principals: images of different view angles are provided to the left and right eyes of the user, so that a stereoscopic image can be perceived by the user. Conventional ways of splitting an image into a left-eye image and a right-eye image generally require the use of a pair of special eyeglasses. Depending on the kind of eyeglasses, stereoscopic projection technologies are roughly classified into the following three types: time multiplexing technologies, polarization technologies and wavelength splitting technologies. Respective advantages and disadvantages of these three kinds of technologies will be briefly described.
In time multiplexing technologies, a common screen, a short-focus projection lens and a pair of active shutter eyeglasses may be used. In polarization technologies, a silver screen, a long-focus projection lens and a pair of passive polarization eyeglasses may be used. The manufacturing cost of the shutter eyeglasses of the former and the silver screen of the latter are very costly, making the cost of these two kinds of stereoscopic projection technologies very high and difficult to provide a cheap and competitive stereoscopic projection apparatus. For wavelength splitting technologies, although a common screen and a pair of passive eyeglasses can be used, use of two projection devices is still necessary to form a stereoscopic image by superimposing two images. Therefore, although the wavelength splitting technology is cost effective in design, it cannot satisfy the requirement for lightweight, low-profile and miniaturized projector apparatuses. However, as solid-state light sources have become increasingly developed over recent years, the aforesaid bottleneck is overcome. In other words, stereoscopic projection technologies that adopted the wavelength splitting technologies have become cost effective and simple practice in the market.
In addition to the needs for cost effective and simple stereoscopic projector apparatuses, more and more consumers now hope that a projector apparatus can switch between displaying a stereoscopic and planar image to meet different needs. Generally, it is known that this can only be accomplished by using a pair of shutter eyeglasses in combination with a display device. However, shutter eyeglasses are relatively costly and degrade the overall luminance with stereoscopic delays. As a result, an additional power source is needed, making it a product that has not been widely accepted by consumers. Accordingly, an urgent need exists in the art to provide a projection module capable of switching between the stereoscopic and planar image mode, as well as a stereoscopic projection system featuring a relatively low cost, simplified optical arrangement, miniaturized volume and improved luminance.